GRA wrote:Now, given the sunk costs, it would make no sense to shut the plant down, unless there's no possibility for improvement.

I wish the taxpayer would underwrite my losses. Sorry, but this has been subsidized from the get-go. It's time to quit throwing money to the wind (er, sun).

GRA wrote:And CSP still has the advantage of storage/load-shifting, while other( inexpensive) storage for renewables has yet to appear in the scale required.

Sorry, but I think you're wrong about this. I will repeat what I just wrote:

RegGuheert wrote:I'm willing to bet that the production into the evening could have been accomplished by simply be building a natural gas peaker plant for that purpose. Likely it would use less natural gas than Ivanpah does.

Perhaps it wasn't clear. If you have to burn a LOT of natural gas to get the thing going each morning, how is that a benefit over simply burning the gas in the evening when you need the electricity? (Ivanpah has had to ask for permission to burn significantly more natural gas than originally planned.)

GRA wrote:Now, given the sunk costs, it would make no sense to shut the plant down, unless there's no possibility for improvement.

I wish the taxpayer would underwrite my losses. Sorry, but this has been subsidized from the get-go. It's time to quit throwing money to the wind (er, sun).

GRA is right. The sunk cost is in. There's no point in shutting it down, keeping it running costs a tiny fraction of what it cost to build. What's keeping the cost of the electricity generated high now is financing. If the plant were allowed to go bankrupt, the taxpayer is very likely the one who would take a bath in this scenario. It's in the taxpayer's best interest for the plant to keep running, even if it's missing it's performance targets.

RegGuheert wrote:Ivanpah has had to ask for permission to burn significantly more natural gas than originally planned.

"Significantly more" than a small amount is still a relatively small amount.

The Ivanpah plant near the California-Nevada border is producing about two-thirds of its annual production goalThe plant’s owners have agreed to pay PG&E an undisclosed sum in exchange for getting time to improve the plant’s electricity output. The deal followed realizations that the plant is failing to meet its production obligations to the utility.

drees wrote:GRA is right. The sunk cost is in. There's no point in shutting it down, keeping it running costs a tiny fraction of what it cost to build. What's keeping the cost of the electricity generated high now is financing. If the plant were allowed to go bankrupt, the taxpayer is very likely the one who would take a bath in this scenario. It's in the taxpayer's best interest for the plant to keep running, even if it's missing it's performance targets.

Taxpayers are only on the hook because of ridiculous loan guarantees made by the government. If the government is forced to repay its own loans, then ownership should revert to the government instead of rewarding the corporation for miserable investment choices.

A better approach would be for the original owners to eat their investment and be forced to sell the plant for pennies on the dollar. Then you will find out if it really makes sense to continue operation. As it stands, you have government bureaucrats spending other people's money with no real accountability in place.

drees wrote:

RegGuheert wrote:Ivanpah has had to ask for permission to burn significantly more natural gas than originally planned.

"Significantly more" than a small amount is still a relatively small amount.

And? That statement in no way invalidates my claim:

RegGuheert wrote:I'm willing to bet that the production into the evening could have been accomplished by simply be building a natural gas peaker plant for that purpose. Likely it would use less natural gas than Ivanpah does.

RegGuheert wrote:It seems clear: PV would have cost significantly less and would have caused significantly less environmental damage, particularly if it had been put on rooftops instead of in the desert.

Dividing up the 377 megawatts into the 140,000 homes it's alleged to support during comes out to 2400 watts per home. Installing 2400 watts of PV on each of those 140,000 homes would cost $8000-8500 per home at 2015 installed prices (pre-subsidy), and would take MUCH less stress off the grid during peak hours than Ivanpah can. That adds up to $1.2 billion, a considerable discount from the $1.6 billion in loan guarantees cited. Spending the difference in up front cost on distributed grid-tied batteries would probably exceed the storage capacity at Ivanpah, and would be far more flexible too.

So, tell me this: Why does the government feel justified in giving massive subsidies to huge multinational corporations to build expensive solar generators that will cause homeowners to pay more money for electricity when instead they could have given the same amount of money BACK to the taxpayers to allow them to nearly eliminate their electricity bills?

No, I'm not in favor of ill-conceived projects like Ivanpah which are, in reality, just hand-outs to corporations to allow them to charge more money from the ratepayers of the utilities.

All of this is taking place at the same time that the utilities in CA are making it much more difficult for homeowners to install PV on their homes.

wwhitney wrote:Burning some natural gas != using natural gas for all of its power generation.

No one ever said that it did. Read it again:

RegGuheert wrote:I'm willing to bet that the production into the evening could have been accomplished by simply be building a natural gas peaker plant for that purpose. Likely it would use less natural gas than Ivanpah does.

The point is that PV plus a natural gas peaker plant could produce the same electricity as the Ivan plant while costing far less money to build, consuming less natural gas, doing far less damage to the environment AND allowing many ratepayers to nearly eliminate their electricity bill instead of raising the rates for ALL ratepayers and ALL taxpayers. Without the irresponsible guarantees provided by the government, this mistake would never have happened because it would not have been funded.

RegGuheert wrote:I'm willing to bet that the production into the evening could have been accomplished by simply be building a natural gas peaker plant for that purpose. Likely it would use less natural gas than Ivanpah does.

The numbers from my previous post make that unlikely. If Ivanpah is averaging 75 lbs CO2/MWh, and a natural gas plant produces 1200 lbs CO2/MWh, then when replacing Ivanpah as a thought exercise only about 75/1200 = 6% of Ivanpah's output could come from a natural gas plant without raising CO2 production.

So what we need is Ivanpah's power production curve over the course of a day. I imagine if you took that curve, and overlaid a PV production curve, the difference in areas would be more than 6%. I.e. you'd need to supplement the PV production with more than 6% natural gas power to match Ivanpah's production curve.

Of course, without Ivanpah's power production curve this is all speculation.

As to whether or not Ivanpah should have been built, I don't have an opinion on that.

That is more than THREE times what you have been told. So why is there a discrepancy? Here is the answer:

Utility Dive wrote:Ivanpah escaped being classified by the CEC as a non-renewable resource because natural gas burned at night to maintain the system is not counted toward its 5% fossil fuel allowance.

According to the CEC, the 10-year-old Pastoria Energy Facility in CA produces electricity from natural gas with CO2 emissions at a rate of 300 kg/MWh (or 661 lbs./MWh).

In other words, the brand new Ivanpah "solar" facility produced 36% as much CO2/MWh in 2014 as a 10-year-old natural gas facility. (Perhaps Ivanpah did better in 2015, but I cannot find the CO2 numbers for 2015.)

As I said, it is much better to install PV and provide for the evening load using natual gas generation. Rooftop PV has the added benefit of REDUCING the load on the grid while centralized generators like Ivanpah increase the load on the grid.

The situation is still not clear. If Ivanpah is burning a lot of natural gas at night to generate electricity at night, well a PV + peak natural gas replacement would still have to do the same.

If you want to compare Ivanpah to a PV + peak natural gas replacement in terms of CO2 production, there's two possible criticisms of Ivanpah. During the day (and early evening?) Ivanpah is using about 6-12% of the CO2 budget a gas plant would use. So if its power production profile is the same as PV, that would all be a waste. But if its power production profile is flatter than PV, it could be that it beats PV + gas peaker during the day.

The other issue is the efficiency at night. If Ivanpah is burning natural gas at night less efficiently than a gas peaker plant, then that extra CO2 would be a waste.

But so far we don't have enough data to answer either of those questions.

wwhitney wrote:The situation is still not clear. If Ivanpah is burning a lot of natural gas at night to generate electricity at night, well a PV + peak natural gas replacement would still have to do the same.

The situation is clear: Ivanpah does not produce electricity at night (beyond early evening). But Ivanpah DOES burn natural gas at night. Assumedly they need to keep the system warm.

Pete Danko wrote:In 2014, Ivanpah used 867 million cubic feet (mmcf) of natural gas. It helps jump start the system in the morning, mostly, and to get through some cloudy periods. At a typical gas-fired power plant, that would produce around 85 gigawatt-hours of electricity. Ivanpah produced 420 GWh in 2014 – so you could say natural gas use was equal to about 20 percent of the plant’s output. This is way over the 5 percent allowed by California regulations, but a California Energy Commission spokesman said much of the natural gas Ivanpah uses isn’t held against it.

“(N)atural gas used between the end of daily generation and the start of generation the next day is not considered as contributing to electricity generation and therefore, not included in calculating the percent of non-renewable fuel used at the facility,” the CEC’s Michael Ward said in an email earlier this month.

Ivanpah’s output jumped up to 652 GWh in 2015, so if natural gas use held steady, the plant’s generation-to-gas-use ratio would have improved substantially. But while we won’t know exactly how much gas Ivanpah used in 2015 for a few months, some hints are available: Between August and November in 2015, gas consumption at one of its three units was double what it was in 2014.

OK, so your bet is looking better, but the situation still isn't clear. We are back to my second post today, except the margin is 20% instead of 6%. If Ivanpah makes enough of its electricity in the evening, it may still be a CO2 win over PV + gas peaker.

If Ivanpah ever adds thermal storage, that could improve its CO2 footprint.